MELBOURNE - A campaign to encourage circumcision among men in sub-Saharan Africa to help protect them against the AIDS virus was backed by new research on Monday showing that men who have had the operation are unlikely to engage in unprotected sex.
Three major trials have previously shown that, for heterosexual men, male circumcision reduces the risk of contracting HIV by as much as 60 percent -- a finding that has prompted the UN's World Health Organization (WHO) to recommend it as a voluntary prevention option, to be used along with the condom.
But some experts have warned that circumcised men, believing themselves to be shielded, are likely to become more promiscuous after the operation, and less likely to wear a condom.
The new study, coinciding with the 20th International AIDS Conference in Melbourne, took a long look at this argument yet found no evidence to support it.
University of Illinois at Chicago researchers questioned more than 3,000 men aged 18-35 in Kenya's Nyanza province who had just been briefed about the option of circumcision and advised on safe sex and testing for HIV.
At the start of the study, half of those enrolled decided to be circumcised, while the others chose to remain uncircumcised. They were asked about their sex life, with followup questions every six months over the following two years.
During this period, sexual activity increased in both groups, especially among those aged 18-24, the investigators found.
But risky sex -- such as having multiple partners or having intercourse in exchange for providing money or gifts -- declined, while use of condoms rose.
Just as revealing was self-perception
Men who were circumcised often believed they had lessened their risk of acquiring HIV. Thirty percent considered themselves high-risk before circumcision, while just 14 percent considered themselves so after.
Among those who decided not to be circumcised, 24 percent considered themselves high-risk at the study's start, and 21 percent still did at the end.
But the different perceptions did not translate into different behaviour, sex-wise.
"Countries that have been holding back on implementing medical circumcision programs due to a lack of evidence regarding risk compensation should have no concerns about scaling-up programs," said lead scientist Nelli Westercamp in a press release issued by the university.
The research appears online in a specialist journal, AIDS and Behavior.
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